Azeotrope-like compositions containing fluoroethane

ABSTRACT

The present invention relates to the discovery of compositions which include fluoroethane, 2-fluoropropane or tert-butylfluoride. These compositions are useful as pure components or with at least one of tetrafluoroethane, difluoroethane, hexafluoropropane, a hydrocarbon or dimethylether. These compositions are useful as aerosol propellants, refrigerants, cleaning agents, expansion agents for polyolefins and polyurethanes, refrigerants, heat transfer media, gaseous dielectrics, fire extinguishing agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.60/029,971, filed Nov. 4, 1996.

FIELD OF THE INVENTION

The present invention relates to the discovery of compositions whichinclude fluoroethane, 2-fluoropropane or tert-butylfluoride. Thesecompositions are useful as pure components or with at least one oftetrafluoroethane, difluoroethane, hexafluoropropane, a hydrocarbon ordimethylether.

These compositions are useful as aerosol propellants, refrigerants,cleaning agents, expansion agents for polyolefins and polyurethanes,refrigerants, heat transfer media, gaseous dielectrics, fireextinguishing agents, power cycle working fluids, polymerization media,particulate removal fluids, carrier fluids, buffing abrasive agents, anddisplacement drying agents.

BACKGROUND OF THE INVENTION

Fluorinated hydrocarbons have had many uses, such as aerosolpropellants, blowing agents and refrigerants. These compounds includetrichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) andchlorodifluoromethane (HCFC-22).

In recent years it has been pointed out that certain kinds offluorinated hydrocarbons released into the atmosphere may adverselyaffect the stratospheric ozone layer. Although this proposition has notyet been completely established, there is a movement toward the controlof the use and the production of certain chlorofluorocarbons (CFCs) andhydrochlorofluorocarbons (HCFCs) under an international agreement.

There is also a demand for aerosol propellants and blowing agents whichhave significantly less photochemical reactivity than hydrocarbons thatcontribute to the formation of ambient ozone and ground level smog.These compounds are typically referred to as low-VOC (volatile organiccompound) or non-VOC.

Accordingly, there is a demand for the development of refrigerants thathave a lower ozone depletion potential than existing refrigerants whilestill achieving an acceptable performance in refrigeration applications.Hydrofluorocarbons (HFCs) have been suggested as replacements for CFCsand HCFCs since HFCs have no chlorine and therefore have zero ozonedepletion potential.

In refrigeration applications, a refrigerant is often lost duringoperation through leaks in shaft seals, hose connections, solderedjoints and broken lines. In addition, the refrigerant may be released tothe atmosphere during maintenance procedures on refrigeration equipment.If the refrigerant is not a pure component or an azeotropic orazeotrope-like composition, the refrigerant composition may change whenleaked or discharged to the atmosphere from the refrigeration equipment.The change in refrigerant composition may cause the refrigerant tobecome flammable or to have poor refrigeration performance.

Accordingly, it is desirable to use as a refrigerant a singlefluorinated hydrocarbon or an azeotropic or azeotrope-like compositionthat includes one or more fluorinated hydrocarbons.

Fluorinated hydrocarbons which are classified as low or non-VOC are alsouseful as aerosol propellants or blowing agents because they do notcontribute significantly to ground level pollution.

Fluorinated hydrocarbons may also be used as cleaning agents or solventto clean, for example, electronic circuit boards. It is desirable thatthe cleaning agents be azeotropic or azeotrope-like because in vapordegreasing operations the cleaning agent is generally redistilled andreused for final rinse cleaning.

Azeotropic or azeotrope-like compositions that include a fluorinatedhydrocarbon are also useful as blowing agents in the manufacture ofclosed-cell polyurethane, phenolic and thermoplastic foams, as heattransfer media, gaseous dielectrics, fire extinguishing agents or powercycle working fluids such as for heat pumps. These compositions may alsobe used as inert media for polymerization reactions, fluids for removingparticulates from metal surfaces, as carrier fluids that may be used,for example, to place a fine film of lubricant on metal parts or asbuffing abrasive agents to remove buffing abrasive compounds frompolished surfaces such as metal. They are also used as displacementdrying agents for removing water, such as from jewelry or metal parts,as resist developers in conventional circuit manufacturing techniquesincluding chlorine-type developing agents, or as strippers forphotoresists when used with, for example, a chlorohydrocarbon such as1,1,1-trichloroethane or trichloroethylene.

SUMMARY OF THE INVENTION

The present invention relates to the discovery of compositions whichinclude fluoroethane, 2-fluoropropane or tert-butylfluoride. Thesecompositions have zero ozone depletion potential (ODP), low globalwarming potential and are lower VOC than hydrocarbons. Thesecompositions are also useful as pure components or with at least one oftetrafluoroethane, difluoroethane, hexafluoropropane, a hydrocarbon ordimethylether. These compositions are used as aerosol propellants,refrigerants, cleaning agents, expansion agents for polyolefins andpolyurethanes, heat transfer media, gaseous dielectrics, fireextinguishing agents, power cycle working fluids, polymerization media,particulate removal fluids, carrier fluids, buffing abrasive agents, anddisplacement drying agents.

Further, the invention relates to the discovery of binary azeotropic orazeotrope-like compositions comprising effective amounts offluoroethane, 2-fluoropropane or tert-butylfluoride and a secondcomponent of tetrafluoroethane, difluoroethane, hexafluoropropane, ahydrocarbon or dimethylether, to form an azeotropic or azeotrope-likecomposition. Azeotropes are highly desirable for refrigerants but notnecessary for aerosol propellants. The compounds of the presentinvention include the following components:

1. fluoroethane (HFC-161, or CH₃CH₂F, boiling point=−38° C.),

2. 1,1,2,2-tetrafluoroethane (HFC-134, or CHF₂CHF₂, boiling point=−20°C.),

3. 1,1,1,2-tetrafluoroethane (HFC-134a, or CF₃CH₂F, boiling point=−26°C.),

4. 1,1-difluoroethane (HFC-152a, or CH₃CHF₂, boiling point=−25° C.),

5. 2-fluoropropane (HFC-281ea, or CH₃CHFCH₃, boiling point=−11° C.),

6. tert-butylfluoride (HFC-3-10-1sy, or (CH₃)₃CF, boiling point=12° C.),

7. 1,1,1,2,3,3-hexafluoropropane (HFC-236ea, or CF₃CHFCHF₂, boilingpoint=6° C.),

8. 1,1,1,3,3,3-hexafluoropropane (HFC-236fa, or CF₃CH₂CF₃, boilingpoint=−1° C.),

9. dimethylether (DME, or CH₃OCH₃, boiling point=−25° C.),

10. butane (CH₃CH₂CH₂CH₃, boiling point=−0.5° C.),

11. isobutane ((CH₃)₃CH, boiling point=−12° C.),

12. propane (CH₃CH₂CH₃, boiling point=−42° C.).

HFC-161 (CAS Reg. No. 353-36-6) and HFC-281ea (isopropyl fluoride, CASReg. No. 420-26-8) have been prepared by reaction of hydrogen fluoridewith ethylene and propylene, respectively, as reported by Grosse and Linin J. Org. Chem., Vol. 3, pp. 26-32 (1938).

2-Fluoro-2-methylpropane (t-butyl fluoride, HFC-3-10-ly, CAS Reg. No.[353-61-7]) may be prepared by the reaction of t-butyl alcohol withaqueous hydrogen fluoride as discussed on page 689 of “Chemistry ofOrganic Fluorine Compounds” by Milos Hudlicky, 2nd. ed., 1976.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/HFC-134a at −14.15° C.;

FIG. 2 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/HFC-152a at −0.05° C.;

FIG. 3 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/HFC-281 ea at −10° C.;

FIG. 4 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/HFC-3-10-1sy at −20° C.;

FIG. 5 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/butane at −20° C.;

FIG. 6 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/isobutane at −10° C.;

FIG. 7 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-161/DME at 0° C.;

FIG. 8 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-281ea/HFC-134a at −10° C.;

FIG. 9 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-281ea/HFC-152a at −10.01° C.;

FIG. 10 is a graph of the vapor/liquid equilibrium curve for mxitures ofHFC-281ea/HFC-3-10-1sy at 0° C.;

FIG. 11 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-281ea/propane at −10° C.;

FIG. 12 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-281ea/DME at −9.95° C.;

FIG. 13 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/HFC-134 at −21.7° C.;

FIG. 14 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/HFC-134a at 0° C.;

FIG. 15 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/HFC-152a at 0° C.;

FIG. 16 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/HFC-236ea at −1.7° C.;

FIG. 17 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/HFC-236fa at −2.5° C.;

FIG. 18 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/butane at 0° C.;

FIG. 19 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3 -10-1sy/isobutane at 0° C.;

FIG. 20 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/propane at −20° C.;

FIG. 21 is a graph of the vapor/liquid equilibrium curve for mixtures ofHFC-3-10-1sy/DME at −10° C.

DETAILED DESCRIPTION

The present invention relates to the following compositions:

-   -   (a) fluoroethane (HFC-161);    -   (b) 2-fluoropropane (HFC-281ea);    -   (c) tert-butylfluoride (HFC-3-10-1sy);    -   (d) HFC-161 and 1,1,1,2-tetrafluoroethane (HFC-134a); HFC-161        and 1,1-difluoroethane (HFC-152a); HFC-161 and 2-fluoropropane        (HFC-281ea); HFC-161 and tert-butylfluoride (HFC-3-10-1sy);        HFC-161 and butane; HFC-161 and isobutane; or HFC-161 and        dimethylether (DME);    -   (e) HFC-281ea and HFC-134a; HFC-281ea and HFC-152a; HFC-281ea        and HFC-3-10-1sy; HFC-281ea and propane; or HFC-281ea and DME;        or    -   (f) HFC-3-10-1sy and 1,1,2,2-tetrafluoroethane (HFC-134);        HFC-3-10-1sy and HFC-134a; HFC-3-10-1sy and HFC-152a;        HFC-3-10-1sy and 1,1,1,2,3,3-hexafluoropropane (HFC-236ea);        HFC-3-10-1sy and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa);        HFC-3-10-1sy and butane; HFC-3-10-1sy and isobutane;        HFC-3-10-1sy and propane; or HFC-3-10-1sy and DME.

1-99 wt. % of each of the components of the compositions are useful asaerosol propellants, refrigerants, cleaning agents, expansion agents forpolyolefins and polyurethanes, refrigerants, heat transfer media,gaseous dielectrics, fire extinguishing agents, power cycle workingfluids, polymerization media, particulate removal fluids, carrierfluids, buffing abrasive agents, and displacement drying agents.Further, the present invention also relates to the discovery ofazeotropic or azeotrope-like compositions of effective amounts of eachof the above mixtures to form an azeotropic or azeotrope-likecomposition.

By “azeotropic” composition is meant a constant boiling liquid admixtureof two or more substances that behaves as a single substance. One way tocharacterize an azeotropic composition is that the vapor produced bypartial evaporation or distillation of the liquid has the samecomposition as the liquid from which it was evaporated or distilled,that is, the admixture distills/refluxes without compositional change.Constant boiling compositions are characterized as azeotropic becausethey exhibit either a maximum or minimum boiling point, as compared withthat of the non-azeotropic mixtures of the same components.

By “azeotrope-like” composition is meant a constant boiling, orsubstantially constant boiling, liquid admixture of two or moresubstances that behaves as a single substance. One way to characterizean azeotrope-like composition is that the vapor produced by partialevaporation or distillation of the liquid has substantially the samecomposition as the liquid from which it was evaporated or distilled,that is, the admixture distills/refluxes without substantial compositionchange. Another way to characterize an azeotrope-like composition isthat the bubble point vapor pressure and the dew point vapor pressure ofthe composition at a particular temperature are substantially the same.

It is recognized in the art that a composition is azeotrope-like if,after 50 weight percent of the composition is removed such as byevaporation or boiling off, the difference in vapor pressure between theoriginal composition and the composition remaining after 50 weightpercent of the original composition has been removed is less than about10 percent, when measured in absolute units. By absolute units, it ismeant measurements of pressure and, for example, psia, atmospheres,bars, torr, dynes per square centimeter, millimeters of mercury, inchesof water and other equivalent terms well known in the art. If anazeotrope is present, there is no difference in vapor pressure betweenthe original composition and the composition remaining after 50 weightpercent of the original composition has been removed.

Therefore, included in this invention are compositions of effectiveamounts of:

-   -   (a) HFC-161 and 1,1,1,2-tetrafluoroethane (HFC-134a); HFC-161        and 1,1-difluoroethane (HFC-152a); HFC-161 and 2-fluoropropane        (HFC-281ea); HFC-161 and tert-butylfluoride (HFC-3-10-1sy);        HFC-161 and butane; HFC-161 and isobutane; or HFC-161 and        dimethylether (DME);    -   (b) HFC-281ea and HFC-134a; HFC-281ea and HFC-152a; HFC-281ea        and HFC-3-10-1sy; HFC-281ea and propane; or HFC-281ea and DME;        or    -   (c) HFC-3-10-1sy and 1,1,2,2-tetrafluoroethane (HFC-134);        HFC-3-10-1sy and HFC-134a; HFC-3-10-1sy and HFC-152a;        HFC-3-10-1sy and 1,1,1,2,3,3-hexafluoropropane (HFC-236ea);        HFC-3-10-1sy and 1,1,1,3,3,3-hexafluoropropane (HFC-236fa);        HFC-3-10-1sy and butane; HFC-3-10-1sy and isobutane;        HFC-3-10-1sy and propane; or HFC-3-10-1sy and DME;    -   such that after 50 weight percent of an original composition is        evaporated or boiled off to produce a remaining composition, the        difference in the vapor pressure between the original        composition and the remaining composition is 10 percent or less.

For compositions that are azeotropic, there is usually some range ofcompositions around the azeotrope point that, for a maximum boilingazeotrope, have boiling points at a particular pressure higher than thepure components of the composition at that pressure and have vaporpressures at a particular temperature lower than the pure components ofthe composition at that temperature, and that, for a minimum boilingazeotrope, have boiling points at a particular pressure lower than thepure components of the composition at that pressure and have vaporpressures at a particular temperature higher than the pure components ofthe composition at that temperature. Boiling temperatures and vaporpressures above or below that of the pure components are caused byunexpected intermolecular forces between and among the molecules of thecompositions, which can be a combination of repulsive and attractiveforces such as van der Waals forces and hydrogen bonding.

The range of compositions that have a maximum or minimum boiling pointat a particular pressure, or a maximum or minimum vapor pressure at aparticular temperature, may or may not be coextensive with the range ofcompositions that have a change in vapor pressure of less than about 10%when 50 weight percent of the composition is evaporated. In those caseswhere the range of compositions that have maximum or minimum boilingtemperatures at a particular pressure, or maximum or minimum vaporpressures at a particular temperature, are broader than the range ofcompositions that have a change in vapor pressure of less than about 10%when 50 weight percent of the composition is evaporated, the unexpectedintermolecular forces are nonetheless believed important in that therefrigerant compositions having those forces that are not substantiallyconstant boiling may exhibit unexpected increases in the capacity orefficiency versus the components of the refrigerant composition.

Substantially constant boiling, azeotropic or azeotrope-likecompositions of this invention comprise the following: WEIGHT RANGESPREFERRED COMPONENTS T° C. (wt. %/wt. %) (wt. %/wt. %) HFC-161/HFC-134a−20 1-99/1-99 10-90/10-90 HFC-161/HFC-152a −30 1-99/1-99 10-90/10-90HFC-161/HFC-281ea −10 73-99/1-27  73-99/1-27  HFC-161/HFC-3-10-1sy −2075-99/1-25  75-99/1-25  HFC-161/butane −20 67-99/1-33  67-99/1-33 HFC-161/isobutane −20 52-99/1-48  52-99/1-48  HFC-161/DME −30 1-99/1-9910-90/10-90 HFC-281ea/HFC-134a −10 1-99/1-99 10-90/10/90HFC-281ea/HFC-152a −20 1-99/1-99 10-90/10-90 HFC-281ea/HFC-3-10-1sy 041-99/1-59  41-99/1-59  HFC-281ea/propane −10  1-41/59-99  1-41/59-99HFC-281ea/DME −9.95 1-99/1-99 10-90/10-90 HFC-3-10-1sy/HFC-134 −21.7 1-44/56-99  1-44/56-99 HFC-3-10-1sy/HFC-134a 0  1-32/68-99  1-32/68-99HFC-3-10-1sy/HFC-152a 0  1-30/70-99  1-30/70-99 HFC-3-10-1sy/HFC-236ea−1.7 11-60/40-89 and 11-60/40-89 and 1-3/97-99 1-3/97-99HFC-3-10-1sy/HFC-236fa −2.5  1-52/48-99  1-52/48-99 HFC-3-10-1sy/butane0 1-99/1-99 10-90/10-90 HFC-3-10-1sy/isobutane 0 1-45/55-99 and1-45/55-99 and 89-99/1-11 89-99/1-11 HFC-3-10-1sy/propane −20 1-19/81-99  1-19/81-99 HFC-3-10-1sy/DME −10  1-42/58-99  1-42/58-99

For purposes of this invention, “effective amount” is defined as theamount of each component of the inventive compositions which, whencombined, results in the formation of an azeotropic or azeotrope-likecomposition. This definition includes the amounts of each component,which amounts may vary depending on the pressure applied to thecomposition so long as the azeotropic or azeotrope-like compositionscontinue to exist at the different pressures, but with possibledifferent boiling points. Therefore, effective amount includes theamounts, such as may be expressed in weight percentages, of eachcomponent of the compositions of the instant invention which formazeotropic or azeotrope-like compositions at temperatures or pressuresother than as described herein.

For the purposes of this discussion, azeotropic or constant-boiling isintended to mean also essentially azeotropic or essentially-constantboiling. In other words, included within the meaning of these terms arenot only the true azeotropes described above, but also othercompositions containing the same components in different proportions,which are true azeotropes at other temperatures and pressures, as wellas those equivalent compositions which are part of the same azeotropicsystem and are azeotrope-like in their properties. As is well recognizedin this art, there is a range of compositions which contain the samecomponents as the azeotrope, which will not only exhibit essentiallyequivalent properties for refrigeration and other applications, butwhich will also exhibit essentially equivalent properties to the trueazeotropic composition in terms of constant boiling characteristics ortendency not to segregate or fractionate on boiling.

It is possible to characterize, in effect, a constant boiling admixturewhich may appear under many guises, depending upon the conditionschosen, by any of several criteria:

-   -   The composition can be defined as an azeotrope of A, B, C (and D        . . . ) since the very term “azeotrope” is at once both        definitive and limitative, and requires that effective amounts        of A, B, C (and D . . . ) for this unique composition of matter        which is a constant boiling composition.    -   It is well known by those skilled in the art, that, at different        pressures, the composition of a given azeotrope will vary at        least to some degree, and changes in pressure will also change,        at least to some degree, the boiling point temperature. Thus, an        azeotrope of A, B, C (and D . . . ) represents a unique type of        relationship but with a variable composition which depends on        temperature and/or pressure. Therefore, compositional ranges,        rather than fixed compositions, are often used to define        azeotropes.    -   The composition can be defined as a particular weight percent        relationship or mole percent relationship of A, B, C (and D . .        . ), while recognizing that such specific values point out only        one particular relationship and that in actuality, a series of        such relationships, represented by A, B, C (and D . . . )        actually exist for a given azeotrope, varied by the influence of        pressure.    -   An azeotrope of A, B, C (and D . . . ) can be characterized by        defining the compositions as an azeotrope characterized by a        boiling point at a given pressure, thus giving identifying        characteristics without unduly limiting the scope of the        invention by a specific numerical composition, which is limited        by and is only as accurate as the analytical equipment        available.

The azeotrope or azeotrope-like compositions of the present inventioncan be prepared by any convenient method including mixing or combiningthe desired amounts. A preferred method is to weigh the desiredcomponent amounts and thereafter combine them in an appropriatecontainer.

Specific examples illustrating the invention are given below. Unlessotherwise stated therein, all percentages are by weight. It is to beunderstood that these examples are merely illustrative and in no way areto be interpreted as limiting the scope of the invention.

EXAMPLE 1 Phase Study

A phase study shows the following compositions are azeotropic, all atthe temperature specified. Press. Vapor Components T° C. Weight Rangespsia (kPa) HFC-3-10-1sy/HFC-134 −21.7 13.9/86.1 14.7 101HFC-3-10-1sy/HFC-236ea −1.7 33.6/66.4 14.7 101 HFC-3-10-1sy/HFC-236fa−2.5 12.7/87.3 14.7 101

EXAMPLE 2 Impact of Vapor Leakage

A vessel is charged with an initial composition at a specifiedtemperature, and the initial vapor pressure of the composition ismeasured. The composition is allowed to leak from the vessel, while thetemperature is held constant, until 50 weight percent of the initialcomposition is removed, at which time the vapor pressure of thecomposition remaining in the vessel is measured. The results aresummarized below. INITIAL 50% LEAK WT % A/WT % B PSIA KPA PSIA KPA DELTA% P HFC-161/HFC-134a (−20° C.)  1/99 19.6 135 19.5 134 0.5 10/90 22.0152 21.2 146 3.6 20/80 24.1 166 22.9 158 5.0 30/70 25.8 178 24.6 170 4.740/60 27.2 188 26.1 180 4.0 50/50 28.3 195 27.5 190 2.8 60/40 29.2 20128.6 197 2.1 70/30 29.9 206 29.5 203 1.3 80/20 30.5 210 30.3 209 0.790/10 30.9 213 30.8 212 0.3 99/1  31.2 215 31.2 215 0.0 HFC-161/HFC-152a(−30° C.)  1/99 11.7 80.7 11.7 80.7 0.0 10/90 12.7 87.6 12.3 84.8 3.120/80 13.8 95.1 13.1 90.3 5.1 30/70 14.9 103 14.0 96.5 6.0 40/60 15.9110 14.9 103 6.3 50/50 16.9 117 15.9 110 5.9 60/40 17.8 123 16.9 117 5.170/30 18.7 129 18.0 124 3.7 80/20 19.5 134 19.0 131 2.6 90/10 20.3 14020.0 138 1.5 99/1  20.9 144 20.9 144 0.0 HFC-161/HFC-281ea (−10° C.)99/1  44.9 310 44.8 309 0.2 90/10 42.7 294 41.1 283 3.7 80/20 40.0 27637.1 256 7.2 73/27 38.1 263 34.3 236 10.0 HFC-161/HFC-3-10-1sy (−20° C.)99/1  31.1 214 31.0 214 0.3 90/10 29.7 205 28.6 197 3.7 80/20 28.1 19425.9 179 7.8 75/25 27.2 188 24.6 170 9.6 74/26 27.1 187 24.3 168 10.3HFC-161/butane (−20° C.) 99/1  31.1 214 31.0 214 0.3 90/10 29.8 205 29.1201 2.3 80/20 28.4 196 26.9 185 5.3 70/30 26.9 185 24.6 170 8.6 67/3326.5 183 23.9 165 9.8 66/34 26.3 181 23.6 163 10.3 HFC-161/isobutane(−20° C.) 99/1  31.2 215 31.2 215 0.0 90/10 30.5 210 30.3 209 0.7 80/2029.6 204 29.0 200 2.0 70/30 28.6 197 27.5 190 3.8 60/40 27.4 189 25.6177 6.6 52/48 26.4 182 23.9 165 9.5 51/49 26.3 181 23.6 163 10.3HFC-161/DME (−30° C.)  1/99 11.6 80.0 11.6 80.0 0.0 10/90 12.4 85.5 12.183.4 2.4 20/80 13.2 91.0 12.7 87.6 3.8 30/70 14.1 97.2 13.3 91.7 5.740/60 15.0 103 14.1 97.2 6.0 50/50 16.0 110 15.0 103 6.3 60/40 17.0 11716.0 110 5.9 70/30 17.9 123 17.1 118 4.5 80/20 18.9 130 18.3 126 3.290/10 19.9 137 19.6 135 1.5 99/1  20.8 143 20.8 143 0.0HFC-281ea/HFC-134a (−10° C.)  1/99 29.1 201 29.0 200 0.3 10/90 26.7 18425.6 177 4.1 20/80 24.4 168 22.7 157 7.0 30/70 22.4 154 20.4 141 8.940/60 20.6 142 18.8 130 8.7 50/50 19.1 132 17.5 121 8.4 60/40 17.8 12316.5 114 7.3 70/30 16.7 115 15.8 109 5.4 80/20 15.7 108 15.1 104 3.890/10 14.9 103 14.6 101 2.0 99/1  14.2 97.9 14.2 97.9 0.0HFC-281ea/HFC-152a (−20° C.)  1/99 17.8 123 17.8 123 0.0 10/90 17.0 11716.6 114 2.4 20/80 16.0 110 15.3 105 4.4 30/70 15.1 104 14.2 97.9 6.040/60 14.2 97.9 13.2 91.0 7.0 50/50 13.3 91.7 12.3 84.8 7.5 60/40 12.485.5 11.6 80.0 6.5 70/30 11.6 80.0 10.9 75.2 6.0 80/20 10.8 74.5 10.270.3 5.6 90/10 10.0 68.9 9.68 66.7 3.2 99/1  9.28 64.0 9.23 63.6 0.5HFC-281ea/HFC-3-10-1sy (0° C.) 99/1  21.0 145 20.9 144 0.5 90/10 20.3140 20.1 139 1.0 80/20 19.6 135 19.1 132 2.6 70/30 18.8 130 18.0 124 4.360/40 17.9 123 16.9 117 5.6 50/50 17.0 117 15.7 108 7.6 41/59 16.1 11114.5 100 9.9 40/60 16.0 110 14.3 98.6 10.6 HFC-281ea/propane (−10° C.) 1/99 35.3 344 49.8 343 0.2 10/90 48.6 335 48.1 332 1.0 20/80 47.1 32545.7 315 3.0 30/70 45.4 313 42.9 296 5.5 40/60 43.4 299 39.3 271 9.441/59 43.2 298 38.9 268 10.0 HFC-281ea/DME (−9.95° C.)  1/99 26.7 18426.7 184 0.0 10/90 25.8 178 25.4 175 1.6 20/80 24.8 171 24.1 166 2.830/70 23.7 163 22.7 157 4.2 40/60 22.5 155 21.3 147 5.3 50/50 21.3 14720.0 138 6.1 60/40 20.0 138 18.7 129 6.5 70/30 18.7 129 17.5 121 6.480/20 17.3 119 16.3 112 5.8 90/10 15.9 110 15.2 105 4.4 99/1  14.4 99.314.3 98.6 0.7 HFC-3-10-1sy/HFC-134 (−21.7° C.) 13.9/86.1 14.7 101.4 14.7101.4 0.0  7/93 14.5 100.0 14.3 98.6 1.4  1/99 13.7 94.5 13.5 93.1 1.5 0/100 13.4 92.4 13.4 92.4 0.0 20/80 14.6 100.7 14.6 100.7 0.0 30/7014.5 100.0 14.2 97.9 2.1 40/60 14.3 98.6 13.5 93.1 5.6 44/56 14.2 97.912.8 88.3 9.9 45/55 14.2 97.9 12.6 86.9 11.3 100/0  3.89 26.8 3.89 26.80.0 HFC-3-10-1sy/HFC-134a (0° C.)  1/99 42.9 296 42.9 296 0.0  5/95 42.3292 42.1 290 0.5 10/90 41.5 286 40.8 281 1.7 15/85 40.6 280 39.4 272 3.020/80 39.7 274 38.0 262 4.3 25/75 38.9 268 36.4 251 6.4 30/70 38.0 26234.7 239 8.7 32/68 37.7 260 34.0 234 9.8 33/67 37.5 259 33.6 232 10.4HFC-3-10-1sy/HFC-152a (0° C.)  1/99 38.4 265 38.4 265 0.0 10/90 36.8 25436.0 248 2.2 20/80 35.0 241 33.1 228 5.4 30/70 33.2 229 30.0 207 9.631/69 33.0 228 29.6 204 10.3 HFC-3-10-1sy/HFC-236ea (−1.7° C.) 33.6/66.414.7 101 14.7 101 0.0 20/80 14.5 100 14.1 97.0 2.9 11/89 13.8 94.9 12.485.5 9.9 50/50 14.6 100 14.3 98.5 1.9 60/40 14.4 99.3 13.2 90.7 8.761/39 14.4 99.3 12.9 88.9 10.4 100/0  8.91 61.4 8.91 61.4 0.0  0/10010.4 71.7 10.4 71.7 0.0  1/99 11.0 75.6 10.5 72.3 4.4  3/97 11.9 81.810.7 73.9 9.7 HFC-3-10-1sy/HFC-236fa (−2.5° C.) 12.7/87.3 14.7 101 14.7101 0.0  1/99 14.2 98.0 14.2 97.8 0.2  0/100 14.1 97.2 14.1 97.2 0.040/60 13.9 95.6 13.2 91.1 4.7 50/50 13.4 92.1 12.2 84.0 8.8 52/48 13.291.3 12.0 82.5 9.7 53/47 13.2 90.9 11.8 81.6 10.2 100/0  8.64 59.6 8.6459.6 0.0 HFC-3-10-1sy/butane (0° C.)  1/99 14.9 103 14.9 103 0.0 10/9014.6 101 14.5 99.8 0.7 20/80 14.2 97.7 14.0 96.4 1.3 30/70 13.7 94.713.5 92.7 2.0 40/60 13.3 91.4 12.9 88.9 2.7 50/50 12.8 87.9 12.3 85.13.2 60/40 12.2 84.1 11.8 81.1 3.6 70/30 11.6 80.0 11.2 77.1 3.7 80/2011.0 75.6 10.6 73.1 3.4 90/10 10.3 70.8 10.0 69.2 2.2 99/1  9.59 66.19.56 65.9 0.3 HFC-3-10-1sy/isobutane (0° C.)  1/99 22.6 156 22.6 156 0.010/90 21.7 150 21.3 147 2.1 20/80 20.7 143 19.8 136 4.3 30/70 19.6 13518.3 126 6.5 40/60 18.4 127 16.8 116 8.8 45/55 17.8 123 16.0 111 9.946/54 17.7 122 15.9 110 10.1 88/12 11.6 80.2 10.5 72.1 10.1 89/11 11.579.0 10.4 71.5 9.5 99/1  9.69 66.8 9.57 66.0 1.2 HFC-3-10-1sy/propane(−20° C.)  1/99 35.2 243 35.0 241 0.6 10/90 33.5 231 31.9 220 4.8 19/8131.6 218 28.6 197 9.5 20/80 31.4 216 28.2 194 10.2 HFC-3-10-1sy/DME(−10° C.)  1/99 26.7 184 26.7 184 0.0 10/90 26.0 179 25.7 177 1.2 20/8025.1 173 24.4 168 2.8 30/70 24.2 167 22.9 158 5.4 40/60 23.2 160 21.1145 9.1 42/58 23.0 159 20.7 143 10.0 43/57 22.8 157 20.5 141 10.1

The results of this Example show that these compositions are azeotropicor azeotrope-like because when 50 wt. % of an original composition isremoved, the vapor pressure of the remaining composition is within about10% of the vapor pressure of the original composition, at a temperatureof 25° C.

EXAMPLE 3 Impact of Vapor Leakage at −20° C.

A leak test is performed on compositions of HFC-3-10-1sy and HFC-236fa,at the temperature of −20° C. The results are summarized below. “A”represents HFC-3-10-1sy and “B” represents HFC-236fa. INITIAL 50% LEAKWT % A/WT % B PSIA KPA PSIA KPA DELTA % P HFC-3-10-1sy/HFC-236fa16.3/83.7 6.86 47.3 6.86 47.3 0.0 10/90 6.82 47.0 6.80 46.9 0.3  1/996.49 44.7 6.47 44.6 0.3 30/70 6.75 46.5 6.66 45.9 1.3 40/60 6.59 45.46.34 43.7 3.8 50/50 6.37 43.9 5.90 40.7 7.4 55/45 6.25 43.1 5.63 38.89.9 56/44 6.22 42.9 5.58 38.5 10.3

These results show that compositions of HFC-3-10-1sy and HFC-236fa areazeotropic or azeotrope-like at different temperatures, but that theweight percents of the components vary as the temperature is changed.

EXAMPLE 4 Vapor Pressures and Kauri-butanol Values

Vapor pressures of the compounds of the present invention are givenbelow. The data indicate these compounds are useful replacements forhydrocarbons widely used in aerosol formulations today. HFC-281ea andisobutane as well as HFC-161 and propane have nearly identical vaporpressures. Kauri-butanol values for the compounds of the presentinvention are also higher than each respective hydrocarbon. Thisindicates these compounds have better solvent capability as well ascompatibility with aerosol resins and other active ingredients. VaporPressure (Psig) Kauri-Butanol 70° F. 130° F. Value HFC-161 106 264 16.3HFC-281ea 31 99 20.3 HFC-3-10-1sy 5 38 — Propane 108 262 15 Isobutane 3197 18 Butane 17 65 20

EXAMPLE 5 VOC (Volatile Organic Compound) Predictions

Kinetic rate measurements were measured experimentally (Jet PropulsionLaboratories) or predicted for compounds of the present invention usinggroup reactivity methodology of R. Atkinson (ref: Kwok, E. S. C., and R.Atkinson, “Estimation of Hydroxyl Radical Reaction Rate Constants forGasPhase Organic Compounds using a Structure-Reactivity Relationship: AnUpdate”, Final Report to CMA Contract No. ARC-8.0-OR, 1994). A compoundcan be considered a potential non-VOC if its kinetic rate at 298 degreesK relative to ethane is less than 1.0. Results are shown in the Tablebelow. TABLE k at 298K cm³/molecule-sec for OH radical k relative toMeasured Compound reaction ethane or predicted Ethane 2.4 × 10⁻¹³ 1.0Measured Propane 1.1 × 10⁻¹² 4.6 Measured Butane 2.54 × 10⁻¹²  10.5Predicted Isobutane 2.33 × 10⁻¹²  9.7 Predicted HFC-161 1.7 × 10⁻¹³ 0.7Measured HFC-281ea 4.6 × 10⁻¹³ 1.9 Measured HFC-3-10-1sy 7.7 × 10-14 0.3Predicted

The compounds of the present invention have significantly reducedphotochemical (hydroxyl radical) reactivity compared to hydrocarbonspropane, butane and isobutane widely used in aerosols today. Using thecompounds of the present invention in aerosols can significantly reduceground level smog. HFC-161 and HFC-3-10-1sy could be classified asnon-VOCs because their reactivity is less than ethane. And HFC-281ea issignificantly less reactive than its hydrocarbon analogue isobutane.

EXAMPLE 6 55% VOC Hair Spray Prototype

A 55% VOC (volatile organic compound) hair spray in accordance with thepresent invention is formulated as follows: TABLE Wt %Octylacrylamide/acrlyates/butylaminoethyl 5.00 methacrylate copolymer(National Starch) AMP (2-amino-2-methyl-1-propanol, Kodak) 0.96Dimethicone silylate (Hydrolabs) 0.50 Water 3.54

To this mixture is added ethanol and propellants of the presentinvention to yield a 55% VOC formulation: Wt % Wt %/Wt % Ethanol HFC-16135.00 55.00 HFC-3-10-1sy 35.00 55.00 HFC-161/HFC-134a 5.00/30.00 55.00HFC-161/HFC-152a 5.00/30.00 55.00 HFC-161/HFC-281ea 35.00/7.00  48.00HFC-161/HFC-3-10-1sy 28.00/7.00  55.00 HFC-281ea/HFC-134a 7.00/35.0048.00 HFC-281ea/HFC-152a 7.00/35.00 48.00 HFC-281ea/HFC-3-10-1sy7.00/35.00 48.00 HFC-3-10-1sy/HFC-134 5.00/30.00 55.00HFC-3-10-1sy/HFC-134a 5.00/30.00 55.00 HFC-3-10-1sy/HFC-152a 7.00/28.0055.00

The vapor pressure of each mixture may vary with formulation. Thisexample is illustrative and does not reflect an optimized system.

EXAMPLE 7 55% VOC Hair Spray Prototype

Two 55% VOC hair sprays in accordance with the present invention areformulated as follows: A B Component Wt % Wt % PVM/MA Copolymer 6.006.00 AMP 0.35 0.35 Water 29.05 38.65 Ethanol 40-1 34.60 25.00

To these mixtures are added 30.00 weight percent of one of the followingcompositions of the present invention to yield a 55% VOC formulation:TABLE Formulation A B Component Wt % Wt % HFC-161/DME 9.60/20.40 —HFC-161/butane 9.60/20.40 — HFC-161/isobutane 9.60/20.40 —HFC-281ea/propane — 9.60/20.40 HFC-281ea/DME — 9.60/20.40HFC-3-10-1sy/butane 9.60/20.40 — HFC-3-10-1sy/isobutane 9.60/20.40 —HFC-3-10-1sy/propane 9.60/20.40 — HFC-3-10-1sy/DME 9.60/20.40 —

The vapor pressure of each mixture may vary with formulation. Thisexample is illustrative and does not reflect an optimized system. Theformulations containing HFC-281ea will have less impact on ground levelsmog than those containing hydrocarbons because HFC-281ea has lesssignificantly less photochemical reactivity.

EXAMPLE 8 Fragrance Prototype

A fragrance in accordance with the present invention is formulated asfollows: TABLE Wt % Fragrance 3.0 Ethanol 40-1 70.0 Water 15.0

To this mixture is added 12.0 weight percent of one of the followingmixtures of the present invention: Wt % % VOC HFC-161 12.0 70 HFC-281ea12.0 82 HFC-3-10-1sy 12.0 70 HFC-161/HFC-134a 3.0/9.0 70HFC-161/HFC-152a 3.0/9.0 70 HFC-161/HFC-281ea 9.0/3.0 73HFC-161/HFC-3-10-1sy 9.0/3.0 70 HFC-161/butane 9.0/3.0 73HFC-161/isobutane 9.0/3.0 73 HFC-161/DME 6.0/6.0 76 HFC-281ea/HFC-134a3.0/9.0 73 HFC-281ea/HFC-152a 3.0/9.0 73 HFC-281ea/HFC-3-10-1sy 3.0/9.073 HFC-281ea/propane 3.0/9.0 82 HFC-281ea/DME 3.0/9.0 82HFC-3-10-1sy/HFC-134  2.0/10.0 70 HFC-3-10-1sy/HFC-134a 3.0/9.0 70HFC-3-10-1sy/HFC-152a 3.0/9.0 70 HFC-3-10-1sy/butane 5.0/4.0 74HFC-3-10-1sy/isobutane 4.0/5.0 75 HFC-3-10-1sy/propane  2.0/10.0 80HFC-3-10-1sy/DME 3.0/9.0 79

The vapor pressure of each mixture may vary with formulation. Thisexample is illustrative and does not reflect an optimized system. Theformulations containing HFC-281ea will have less impact on ground levelsmog than those containing hydrocarbons because HFC-281ea has lesssignificantly less photochemical reactivity.

EXAMPLE 9 Aerosol Antiperspirant Prototype

A 60% VOC aerosol antiperspirant in accordance with the presentinvention is formulated as follows: TABLE Wt % Aluminum chlorohydrate10.0 Isopropyl myristate 6.0 Silicone fluid DC-344 6.0 (Dow Corning)Talc 0.5 Quaternium-18 hectorite 0.5 Ethanol 40-1 2.0

To this mixture is added 75.0 weight percent of one of the followingmixtures of the present invention to yield a 60% VOC formulation:HFC-161/DME 17.0/58.0 HFC-161/butane 17.0/58.0 HFC-161/isobutane17.0/58.0 HFC-3-10-1sy/butane 17.0/58.0 HFC-3-10-1sy/isobutane 17.0/58.0HFC-3-10-1sy/propane 17.0/58.0 HFC-3-10-1sy/DME 17.0/58.0

Similar formulations can also be developed for air fresheners, householddisinfectants, insect foggers and spray paints using the compositions ofthe present invention.

EXAMPLE 10 Hair Spray Performance

The following example demonstrates efficacy of the patent invention inhair sprays, compared to a widely used hydrofluorocarbon propellant HFC-152a (CH₃CHF₂) as shown in the table below. The formulations were onephase indicating complete miscibility. Tack and dry times, curl droop,and flame extension tests were used to evaluate performance. Curl droopmeasures the percent lengthening of a curl five minutes after spraying.Flame extension was measured to determine the flammability of eachformulation. Results show each formulation achieved 80% or higher curlretention, good tack and dry times, and acceptable flame extensionsdespite the fact that the formulations were not optimized. TABLEComponent Formulation (Wt %) A B C D E F G H Resin* 25 25 25 25 25 19.519.5 19.5 Ethanol 43 43 43 43 43 35.0 35.0 35.0 Additives 2 2 2 2 2 1.71.7 1.7 HFC-161 — 30 — 18 — — — 10.0 HFC-281ea — — 30 — 12 — 10.0 —HFC-152a 30 — — — 18 10.0 — — Butane — — — 12 — — — — Water — — — — —13.8 13.8 13.8 DME — — — — — 20.0 20.0 20.0 Total Wt % 100 100 100 100100 100 100 100 Vapor Pressure 60 95 31 79 52 47 40 64 @ 70° F. (psig) %VOC 43 43 73 55 55 55 65 55 Curl droop % 9 21 11 17 16 18 11 17 TackTime 10 14 4 7 11 8 14 58 (sec) Dry Time (sec) 24 28 17 46 54 21 39 73Flame 4 6 9 4 13 4 12 16 Extension (inches)*t-butylacrylate/ethylacrylate/methacrylic acid copolymer resin

EXAMPLE 11 Air Freshener Performance

To test air freshener flammability and miscibility, compositions of thepresent invention were formulated into air fresheners as shown in thetable below. The formulations were one phase indicating completemiscibility. Flame extensions were measured which were less than 18inches, the desirable maximum. The formulations showed good spraypatterns and delivery. TABLE Formulation A B Component Wt % Wt %Fragrance 1 1 Water 4 4 Ethanol 30 30 HFC-161 65 — HFC-281ea — 65 TotalWt % 100 100 Vapor Pressure @ 70 F. 106 33 (psig) Flame Extension (in)13 16

EXAMPLE 12 Fragrance Performance

To test fragrance flammability and miscibility, compositions of thepresent invention were formulated into fragrances as shown in the tablebelow. The formulations were one phase indicating complete miscibility.Flame extensions were then measured which were less than 18 inches, thedesirable maximum. The formulations showed good spray patterns anddelivery. TABLE Formulation A B Component Wt % Wt % Fragrance 3 3Ethanol 70 70 Water 15 15 HFC-161 12 — HFC-281ea — 12 100 100 VaporPressure @ 70 F. 46 14 (psig) Flame Extension (in) 13 10

EXAMPLE 13 Shelf Life Stability

Compositions shown in the table below were prepared and loaded intotin-plate aerosol cans. Cans were placed in an oven at 120° F. or heldat room temperature (21-23° C.) for several months. TABLE CompositionTemperature Time Can Interior HFC-161/Ethanol 120° F.  2 months Nocorrosion (30/70 wt %) Slight detinning  6 months No corrosion Mediumdetinning FC-161/Ethanol Room 24 months No corrosion (30/70 wt %) Slightdetinning HFC-281ea/Ethanol 120° F.  1 month No corrosion (60/40 wt %)or detinning  3 months No corrosion or detinning HFC-281ea/Ethanol/ 120°F.  1 month No corrosion Water (40/54/6 wt %) or detinningAs shown in the table, the propellant compositions demonstrated goodstability in formulation solvents, even without corrosion inhibitors.

EXAMPLE 14

The following table shows the performance of various refrigerants. Thedata is based on the following conditions. Evaporator temperature  45.0°F. (7.2° C.) Condenser temperature 130.0° F. (54.4° C.) Subcooled  15.0°F. (8.3° C.) Return gas  65.0° F. (18.3° C.)Compressor efficiency is 75%.

The refrigeration capacity is based on a compressor with a fixeddisplacement of 3.5 cubic feet per minute and 75% volumetric efficiency.Capacity is intended to mean the change in enthalpy of the refrigerantin the evaporator per pound of refrigerant circulated, i.e. the heatremoved by the refrigerant in the evaporator per time. Coefficient ofperformance (COP) is intended to mean the ratio of the capacity tocompressor work. It is a measure of refrigerant energy efficiency. EvapCond Capacity Refrig Press Press Comp. Dis BTU/min Comp. Psia (kPa) Psia(kPa) Temp. ° F. (° C.) COP (kW) HFC-161/HFC-134a  1/99 55 379 215 1482171 77 3.43 225 4.0 99/1 80 552 279 1924 201 94 3.49 316 5.6HFC-161/HFC-152a  1/99 51 352 194 1338 204 96 3.60 224 3.9 99/1 90 552278 1917 200 93 3.53 318 5.6 HFC-161/HFC-281ea  1/99 27 186 106 731 16876 3.71 123 2.2 99/1 79 545 278 1917 201 94 3.49 314 5.5HFC-161/HFC-3-10-1sy  1/99 13 90 55 379 148 64 3.75 63 1.1 99/1 79 545277 1910 201 94 3.50 314 5.5 HFC-161/butane  1/99 20 138 82 565 155 683.68 93 1.6 99/1 79 545 277 1910 201 94 3.49 314 5.5 HFC-161/isobutane 1/99 30 207 65 448 112 44 3.57 123 2.2 99/1 79 545 279 1924 201 94 3.49315 5.5 HFC-161/DME  1/99 49 338 183 1262 194 90 3.67 215 3.8 99/1 79545 279 1924 201 94 3.49 315 5.5 HFC-218ea/HFC-134a  1/99 54 372 2121462 171 77 3.43 222 3.9 99/1 27 186 105 724 168 76 3.70 121 2.1HFC-281ea/HFC-152a  1/99 50 345 192 1324 204 95 3.61 222 3.9 99/1 27 186105 724 168 76 3.70 122 2.1 HFC-281ea/HFC-3-10-1sy  1/99 12 83 54 372148 64 3.68 59 1.0 99/1 26 179 104 717 168 76 3.70 120 2.1HFC-281ea/propane  1/99 83 572 270 1862 166 74 3.32 282 5.0 99/1 27 186107 738 168 76 3.71 123 2.2 HFC-281ea/DME  1/99 48 331 181 1248 193 893.68 213 3.8 99/1 27 186 106 731 168 76 3.70 122 2.1HFC-3-10-sy/HFC-134a  1/99 42 290 167 1151 182 83 3.60 187 3.3 99/1 1283 54 372 148 64 3.69 60 1.1 HFC-3-10-1sy/HFC-134a  1/99 54 372 210 1448171 77 3.44 221 3.9 99/1 12 83 54 372 148 64 3.69 60 1.1HFC-3-10-1sy/HFC-152a  1/99 50 345 191 1317 203 95 3.60 221 3.9 99/1 1390 54 372 148 64 3.70 60 1.1 HFC3-10-1sy/HFC-236ea  1/99 15 103 70 483143 62 3.50 71 1.3 99/1 12 83 53 365 148 64 3.67 59 1.0HFC-3-10-1sy/HFC-236fa  1/99 20 138 86 593 141 60 3.42 86 1.5 99/1 12 8353 365 148 64 3.67 59 1.0 HFC-3-10-1sy/butane  1/99 19 131 80 552 155 683.65 90 1.6 99/1 12 83 53 365 148 64 3.67 59 1.0 HFC-3-10-1sy/isobutane 1/99 29 200 110 758 152 67 3.56 120 2.1 99/1 12 83 54 372 148 64 3.6859 1.0 HFC-3-10-sy/propane  1/99 83 572 269 1855 166 74 3.33 281 4.999/1 13 90 55 379 147 64 3.74 62 1.1 HFC-3-10-1sy/DME  1/99 48 331 1811248 193 89 3.67 213 3.7 99/1 13 90 55 379 148 64 3.73 62 1.1

Additional Compounds

Other components, such as aliphatic hydrocarbons having a boiling pointof −60 to +60° C., hydrofluorocarbonalkanes having a boiling point of−60 to +60° C., hydrofluoropropanes having a boiling point of between−60 to +60° C., hydrocarbon esters having a boiling point between −60 to+60° C., hydrochlorofluorocarbons having a boiling point between −60 to+60° C., hydrofluorocarbons having a boiling point of −60 to +60° C.,hydrochlorocarbons having a boiling point between −60 to +60° C.,chlorocarbons and perfluorinated compounds, can be added to theazeotropic or azeotrope-like compositions described above withoutsubstantially changing the properties thereof, including the constantboiling behavior, of the compositions.

Additives such as lubricants, corrosion inhibitors, surfactants,stabilizers, dyes and other appropriate materials may be added to thenovel compositions of the invention for a variety of purposes providesthey do not have an adverse influence on the composition for itsintended application. Preferred lubricants include esters having amolecular weight greater than 250.

1-23. (canceled)
 24. An azeotropic or azeotrope-like compositionconsisting essentially of: 52-99 weight percent fluoroethane and 1-48weight percent isobutane wherein when the temperature of saidcomposition has been adjusted to about −20° C., said composition has avapor pressure of about 26.4 psia (182 kPa) to about 31.2 psia (215kPa).
 25. A process for producing aerosol products comprising adding asa propellant a composition of claim 24 to an aerosol container.
 26. Aprocess for producing refrigeration comprising condensing a compositionof claim 24 and thereafter evaporating said composition in the vicinityof a body to be cooled.
 27. A process for preparing a thermoset orthermoplastic foam comprising using a composition of claims 24 as ablowing agent.